Pneumatic tire for passenger cars

Abstract

A pneumatic tire for passenger cars having at least one carcass ply extending between right and left beads through a tread, the at least one carcass ply having reinforcing cords that extend in the radial direction of the tire and are disposed at predetermined intervals in the circumferential direction of the tire, a plurality of belt plies being placed radially outwardly of the at least one carcass ply in the tread. A bead core is embedded in each of the right and left beads and a bead filler is disposed radially outwardly of the bead core, the bead filler having a radially outer edge that is located at a position closer to the radially inner side of the tire than a position of 50% of the section height of the tire. The mean residual strain of the reinforcing cords ranges from −10% to 3% in a portion of the at least one carcass ply located in a region from each of the opposing edges of the widest belt ply of the plurality of belt plies to a position that is 30 mm away widthwisely inwardly of the tire therefrom.

1 . A pneumatic tire for passenger cars having right and left beads, a bead core being embedded in each of the beads, a bead filler being disposed radially outwardly of the bead core, the bead filler having a radially outer edge that is located at a position closer to an radially inner side of the tire than a position of 50% of a section height of the tire, at least one carcass ply extending between the right and left beads through a tread, the at least one carcass ply having reinforcing cords that extend in a radial direction of the tire and are disposed at predetermined intervals in a circumferential direction of the tire, a plurality of belt plies being placed radially outwardly of the at least one carcass ply in the tread, 
 wherein a widest belt ply of the plurality of belt plies has opposing edges, the reinforcing cords of the at least one carcass ply having mean residual strain, the mean residual strain being −10% to 3% in a portion of the at least one carcass ply located in a region from each of the opposing edges to a position that is 30 mm away widthwisely inwardly of the tire therefrom.    
   
   
       2 . A pneumatic tire for passenger cars according to  claim 1 , wherein the mean residual strain of the reinforcing cords is −10% to 2% in the portion of the at least one carcass ply.  
   
   
       3 . A pneumatic tire for passenger cars according to  claim 2 , wherein the mean residual strain of the reinforcing cords is −10% to 0% in the portion of the at least one carcass ply.  
   
   
       4 . A pneumatic tire for passenger cars according to  claim 1 , wherein the radially outer edge of the bead filler is located at a position closer to the radially inner side of the tire than a position of 45% of the section height of the tire.  
   
   
       5 . A pneumatic tire for passenger cars according to  claim 4 , wherein the radially outer edge of the bead filler is located at a position closer to the radially inner side of the tire than a position of 40% of the section height of the tire.  
   
   
       6 . A pneumatic tire for passenger cars according to  claim 1 , wherein the at least one carcass ply comprises a first carcass ply and a second carcass ply disposed outwardly of the first carcass ply, the first carcass ply having opposing ends each turning up around the bead core from an inner side of the tire toward an outer side thereof, the second carcass ply having opposing ends each extending inwardly from an outer side of the bead core.  
   
   
       7 . A pneumatic tire for passenger cars according to  claim 1 , wherein the plurality of belt plies include a first belt ply adjacent to the at least one carcass ply and a second belt ply disposed radially outwardly thereof, the widest belt ply being the first belt ply.  
   
   
       8 . A pneumatic tire for passenger cars according to  claim 1 , the reinforcing cords of the at least one carcass ply is formed from organic fiber cords.